The present invention relates generally to agricultural machinery and, more particularly, to improvements to steering systems of operator-driven agricultural machines. The invention concerns a device for controlling a double-acting steering cylinder of a steering system with two working connections which are each connected to a valve unit.
A device for controlling a double-acting steering cylinder of machine steering systems, known from German Patent 195 39 088 A1, has a valve unit which comprises two proportional valves. With proportional driving of the valves, relatively accurate displacement of a piston in the steering cylinder can be accomplished. Disadvantages of that device is that it is relatively slow, and driving the proportional valves requires relatively elaborate measures.
It is therefore the object of the present invention to overcome one or more of the deficiencies described above.
It is another object to provide a device for controlling a double-acting steering cylinder which has a simple construction and with which a rapid reversal of the direction of steering in the steering cylinder can be obtained.